intermittent thoughts on my life and work as the chess coach at IS 318, a public middle school in Brooklyn

Saturday, October 3, 2009

a few tactics from today's scholastic tournament

Lequasiah Lawrence went 4-0 and won the reserve section. Her fourth round game reached the following position:

Lequaisiah's white. Do any of her attacking tries (9. Nf6, 9. Qg4, 9. Qh5, 9. Bxh6) work? Which is best?

same game. White to move?

Henry Cali's last move, 7. Bc4, was a mistake.Where should his opponent (black) have moved?His opponent actually played 7... Qd8. How does that lose tactically?Does 7... Qd6 lose to the same tactic?

Sebastian Dabrowski won his first three games before losing to 3rd place finisher and 318 alumnus Rochelle Ballantyne. What classic tactic did Sebastian (white) find against (also 318 alum!) Ezequiel Quinones?

12 comments:

1st position. White's problem is that the h7 knight is trapped, e5 is hanging, and Black can play Ng6 to stop mating threats. I don't see a win for White. Probably the best practical chance is 1.Qh5.

2nd position. White would like to capture the enemy queen, but unfortunately the knight is pinned against the back rank mate. This suggests something like 1.Bxh6, which defends e1, and thus "arms" the threat to the Black queen. If 1...Qd7, then 2.Bxg7+ looks decisive.

3rd position. I don't see anything better than 1...Qe4+ 2.Be2 Bxf3 3.gxf3, leaving White with weak pawns. 1...Qd8? is a mistake because it allows 2.Bxf7+ (2...Kxf7 3.Ng5+ followed by 4.Qxg4) winning a pawn. 1...Qd6 is different because Black threatens the tactic Qe5+, winning the rook on a1.

1. She played 10. Qg4, but this is just bad because of 10… Nxe5. Going over the game, I thought 10. Nf6 was practically winning: 10… gxf6 11. Qg4+ Ng6 12. Bxg6 fxg6 13. Qxg6 Kh8 14. Qxh6 Kg8 15. Qg6 Kh8 16. exf6 or 11… Kh8 12. Bxh6. Practically, it is winning, but in a perfect world black has two defenses. In the first line, 12… Nxe5 saves black, and in the second, black is actually already ok with perfect defense: 12… Ng6 13. Qh5 Ncxe5. 10. Qh5 is also great -- of course fritz can defend, but no kid will find a good way to deal with the threat of 11. Bxh6. 10. Bxh6 seems a little less dangerous to me?